1. Field of Invention
This invention relates to dental implements, specifically to a dental separator for applying pressures against adjacent teeth to force the teeth apart from one another. In particular, this invention relates to temporary dental implements for enlarging the space between adjacent teeth as necessary for various dental procedures such as dental restorative treatments and applying dental matrices, dental matrix shims and orthodontic bands. The invention also relates to a dental implement which may, in addition to forcing adjacent teeth apart, be used to stabilize dental matrices.
2. Description of Related Art
When tooth decay occurs in a zone proximal an abutting tooth, thin bands or shims, commonly known as dental "matrices", are wrapped around the tooth being treated. The matrix provides a temporary form which will hold fluid restorative material in a controlled shape until the restorative material cures. Thin bands are also wrapped around teeth in order to grasp and reposition teeth relative to neighboring teeth of a dental arch for orthodontic treatments. Space to accommodate the thickness of such bands and shims between abutting teeth must be generated by mechanically forcing the abutting teeth apart.
It is well known that treating a tooth without separating it from its abutment tooth may create an unnatural and troublesome configuration between the treated tooth and the abutment tooth causing a pathologic response from the surrounding tissues. In the interest of providing healthful services, dentists must recreate firm tooth-to-tooth contact as is natural in dental arches and important to dental health. To accomplish appropriate contact, the involved teeth must be forced apart temporarily to create a sufficient space for the thickness of a dental matrix and to allow proper shaping of restorative material as it cures.
Once a dental matrix is positioned between involved teeth, the matrix must be stabilized to allow the dentist to manipulate its contours without dislodging it. For example, some restorative materials, notably silver amalgam alloys, must be scrubbed into a prepared void of the treated tooth with force, thus requiring rigid stabilization of the dental matrix to resist disfigurement of its contours during such scrubbing in order to prevent resulting disfigurement of the treated tooth.
Various devices have been used to spread adjacent teeth, most commonly, a wedge of wood or plastic is forced into the interdental or proximal space. Such wedges forced into the triangular void between teeth disadvantageously develop a vertical force vector as well as the intended horizontal separating force vector. The undesirable vertical force vector often traumatizes the gum tissue at the base of the triangular void.
U.S. Pat. Nos. 4,601,662 and 4,718,852 to Galler are directed to a screw impelled vise forcing elements between and against teeth. This device disadvantageously loses its spreading influence after the teeth yield to a first pressure increment and thus requires sequential increments to extend the separating influence. The Galler device is inserted into the triangular void or interproximal triangle between teeth and disadvantageously creates undesirable vertical force vectors. As the elements are forced into the interproximal triangle, the device vertically presses against and traumatizes soft gum tissues at the base of the interproximal triangle.
U.S. Pat. No. 1,336,746 to Ivory discloses a rubber dam clamp which engages a single tooth along lingual and buccal surfaces of the tooth. The Ivory device does not contact interdental surfaces between abutting teeth and will not provide a separation force between abutting teeth.
Similar to the Ivory device, U.S. Pat. Nos. 2,706,333 to Schultz, 4,004,345 to Ely, 4,265,623 to Soelberg et al, 4,639,221 to Sairenji, 4,661,063 to Levy, and 4,787,849 to Jacoby et al. each disclose a device which engages a single tooth along lingual and buccal surfaces of the tooth. Similarly, these devices do not contact interdental surfaces between abutting teeth and do not provide a separation force between abutting teeth.
U.S. Pat. No. 5,503,556 to Leonard et al. discloses a device which extends along abutting teeth, however, the interior arcuate surface of the Leonard device engages along lingual and buccal surfaces of a single tooth instead of interdental surfaces between abutting teeth. Thus, the Leonard device does not provide a separation force between abutting teeth.
U.S. Pat. No. 5,199,869 to McGann and U.S. Pat. No. 5,314,331 to Broslus et al. each disclose orthodontic wire springs placed between adjacent teeth perpendicular to the occlusal plane with wires extending into and occupying the proximal space between the adjacent teeth. Although the McGann and Broslus devices apply a tooth spacing force on adjacent teeth during orthodontic treatment, such devices are not conducive to restorative dental procedures because the wire springs occupy the very work space required for such dental procedures.
U.S. Pat. No. 5,607,302 to Garrison discloses an apparatus for retaining a dental matrix against a tooth. The disclosed matrix retainer apparatus is not designed to separate adjacent teeth. Instead, Garrison discloses discrete wedges, which are used in combination with the matrix retainer apparatus, to separate adjacent teeth.
U.S. Pat. No. 4,373,915 to Comstock discloses an iatrogenic shield having sufficient elasticity to deform for placement against a tooth to be protected wherein its side walls contract against the buccal and lingual surfaces of the tooth. The Comstock device is sufficiently thin to pass between the interproximal surfaces of adjacent teeth, however the device is not designed to generate a force for separating adjacent teeth.
U.S. Pat. 5,975,906 to Knutson discloses a soft polymer dental strip similar to PTFE thread seal tape commonly found in plumbing stores. The dental strip is an over-wrap designed to cover freshly applied restorative material until the material is cured.
Circular spring clips have been known to the dental profession as teeth separating devices. They were engaged by spreading forceps at two mid-points across the diameter of a circular yoke. As such spring clips are stretched, distention is limited to the proximal half of the yoke whereby the distal half does not contribute to the spring bias of the clip. A disadvantage of such known spring clips is that distention is limited to the proximal half of the yoke which may cause permanent distortion of the device and a loss of effectiveness. Another disadvantage is that teats of a spreading tool engage such known spring clips at lateral surfaces of the circular yoke thus creating an axis about which the device may rock resulting in increased difficulty in exact placement of the device against teeth.